Channels that broadcast on the VHF band are also much more prone to interference from various electrical and electronic equipment than those using UHF. This vulnerability is kind of a flaw in the ATSC system the US chose for digital television, and so preferred bands are now opposite to how things were in the analog era, when VHF (channels 2-13) usually had better reception.
One of my Roku TVs has an issue where when a weak VHF station does get briefly disrupted by interference (e.g. from a freezer cycling on/off in the room), sometimes it will get out of sync with the stream and continue showing artifacts even after interference has ceased. In this case, changing to another channel, then back solves the problem. I've only seen that happen twice, but hopefully a future software update will help.
It's no longer possible to tell what frequency a particular station uses by its channel number, due to a remapping table that allowed stations to keep their old numbers despite moving around the spectrum. e.g. in my area there is a "Channel 4" that's actually on UHF (physical channel 18) and always has excellent reception, while our "Channel 25" is VHF (physical channel 10) and sees occasional interference. rabbitears.info is one good site for looking up the true physical channel being used for a station of interest. tvfool.com had been a good one in years past, but seems not to have been updated to account for recent "repacking" frequency changes, where many stations had to move to make room for more cell phone spectrum. The FCC's site has this information too, but is harder to navigate.
